Underreamer.



C. E. FRBDERICKSON.

UNDERREAMER.

APPLIGATION FILED SEPT. 19, 1911.

Patented 11011.26, 1912.

3 SHEETS-SHEET 1.

C. E. FREDERIGKSON.

UNDBRREAMER. APPLICATION FILED SEPT. 19. 1911.

Patented Nov. 26, 1912 3 SHEETS-SHEET 2.

Wl T/VESSES:

G. E. FREDERIGKSON'.

UNDERRBAMER.

APPLICATION FILED SEPT. 19, 1911.

i Patented NOV. 26, 1912.

3 SHEETS-SHEBT 3.

vtIILlZTUN FREDERCKSON, OF SN FRANCISCO, GALIFQRNKA.v y p nnnnnianniuna.

Specification of Letters Patent.

Patenten Nov. ae., tera.

Application filed September 19, 19111. Serial'No. 650,110.

'lo @ZZ volli-om it may concern: i,

Be 1t known that I, CLAYTON E. FRED- ERiCKsoN, of San Francisco, 1n the county Vof San Francisco and State of California,

have inventedxa certain new and useful lmprovement 1n Underreamers, of which the vfollowing is a specification.

My invention is an improved tool for use in drilling and boring oil wells: I

ln practice a well tube or casing is forced .into the well, and in order that the casing or tube may pass down, the well must be reamed out below the tube as it moves downwardly. In accomplishing this act., the tools em vloyed', not infrequently become jammed, bro ren, and lost, thereby rendering theoperation of well drilling bothv uncertain and expensive, and furthermore delaying the operations until the lost tool is recovered and removed from the well, or

drilled into metallic dust or driven into a soft formation outside of the wall of'the well.

lt is therefore the principal object of the present invention to provide a reaming tool that canfbe readily admitted orvit'hdrawn through the well casing without delay, and

,Y without danger of jamming the tool in the casing. .l

The invention also consists in constructing the upper ends of the cutters with' trunnions and forming slots or pockets in the supportingbody, providing such body with grooves that communicate with t-he pocket and placing the cutters in posit-ion by inserting the trunnion end of the cuttersLirst in the main body and pushing the same into place, and then turning the cutters on their trunnions and dropping or forcing them into the grooves and final restp ing place for the cutters.

it impossible for 'The invention also includes a structure whichhas provisions whereby in the event of any accident by breaking the cross-key or actuating rod. or spring, the cutters will drop down the grooves in which the trunnions are located, until the trunnions rest at the bottom ofthe grooves, thus making the cuttersto escape from the Amain body in case of accident.

-In applying my invention, I provide a body aving cutter receiving chambers'or pockets in which the cutters are so located and mounted as to protect the cutting edges folded or telescoped position..

beyond the diameter of the body when in use to under-ream or undercut the well wall beneath the descending tube. The body and cutters are linterlocked when in operation,

in such manner however, that upon exerting In its more subordinate nature, the invention includes those novel details of construction, combination and .arrangement of parts, all of which will be first fullydescribed and then be specifically pointed out in the appended claims, reference being had to the accompanying drawings, in which,

Figure l is a central vertical longitudinal section of the lower end of a well tube, showing the invention in use, the reamer being shown in elevation. Fig.' 2 is a side elevation of the tool with the parts in the Y Fig. 3 is a vertical section with the parts positioned as in Fig. 2. .Fig. 4 is a vertical section with the parts in their operative position. Fig. 5 is a cross section on the line 5;-5 of Fig. 4. F ig. 6 is an elevation at right angles to Fig. 1. Fig. 7 is an inverted plan view of the parts shown in Fig. t. Fig. 8 is a de- `tail view of one of the cutters showing the removable cutter point. Fig. 9 is a view partly in elevation and partly in central vertical longitudinal section of another form of the invention. Fig. l0 is a cross section on the line 10`l0 of Fig. 9. 'Fig l1 is a cross section on the line 11-11 of Fig. 9. Fig. 12 is a detail perspective view of one of t-he cutters used in the latter form of the invention.

ln the drawings in which like numerals and letters of reference indicate like parts in all of the figures; 1 designates the main portion of the body, which has a threaded boss 2 and is bored at 3 to receive the spring 4 that surrounds the stem 5. The stem 5 projects into a bore- 6, that communicates vbers 9-9. Near its lower with the slot 7 which passes through the web 8, the web 8 separating the two cutter chamend, the. web'8 has shoulders 10, and the extreme lower end of the body 1 is V-shaped as at 11 and is provided with an inverted V-shaped recess 12 at each side .of the central V-shaped portion 11 to receive the correspondingly shaped head 13 of the cutters 14. Each cutter 14 consists of a body web 15, that is slotted at 16 to receive the cross/key 17 which is secured to the lower end of the rod 5 and passes through the slot 7. The side walls of the cutter chambers 9 are provided with L-grooves 18, one end of each of `which opens out at the side of the body, while the other endy is blind as best` indicated in Fig. 4. TheI grooves 18 receive the trunnion bearings 19 of the cutters 14. Each cutter -14 has a shoulder 20 that opposes the correspondin shoulder 10, for a purpose hereinafter c early set forth. Each cutter 14 also has a point receiving recess 21, the

l24 is held in place upper wall of which is provided with a dove tail slot 22 to receivey the dove tail 23 of the removable fpoint 24. The point by a pin 25 that passes through the cutter tail 22 as best sho-wn in Fig. 4.

26 is a union-cap a threaded pocket 27 for the boss 2, and it also has a bore 28 that communicates with the pocket and receives the spring 4 and the rod 5. The union-cap 29 and a threaded pin 30 d 31. Operation: The well tube 32 having been to screw into the i started into the well opening, the reamer time they are folded in to is let down into position. This is accomplished by pulling the cutters 14 downwardly yunt-il the trunnions 19 rest in the blind ends of the grooves 18, at which lie within the diameter of the body endof the reamer, and

they are held in this position against ten-V sion of the spring 4 by breakable pieces 33, of wood or other similar material, that are placed between the shoulders 10 and 2O as best indicated in Fig. 3. 'Ihe tool is then lowered through the well tubeJ 32, and when the 'cutters' engage the lbottom of the well opening the rods 33 will break, and permit 'the spring 4 to draw the cutters in to the operative position l indicated in Fig. 4, the spring 4being aided in this function by the weight of the body 1 and its carried parts. When it is desired to remove the tool from the well, it is only necessary to draw up on the stem 31,.when the inclined faces 34 of the cutters will engage the lower end of the r`well .tube and be forced to telescope into the diametrical dimension of the body 1, and thereby ,readily pass through the well tube without danger of sticking or jam'- ming.

open at theoutside of the head 13 and the dove.

whichis provided with 26 has a nut'face In Fig. 9l et seg., I have shown andther,

and perhaps simpler form ofthe invention. In this form the body 1iL is provided with the threaded pin 310a to receivefthe stem or rod 31, and the union-cap 26 is omitted. The body the spring 4a and the rod 5a. a restricted portion V6a to form the spring 1a is bored, at 3-3", to receive I The bore has abutment. As in the form shown in Figs.

1 to 8 inclusive, so in this form, the body 1a has cutter pockets 9*1 and trunnion receiving grooves 18a-*18", one end of each groove being blind and the other end ,y body. The open arm 18b of each groove is of less width than thel diameterl ofthe trunnion 19a, so as to retain the cutter 15a and prevent its dropping out or becoming disconnected from the body 1*L accidentally. In order thatthe cutters may be entered into position, the trunnions are flattened or cut away as at 19D, so that they may be inserted, as indicated in heavy dotted lines in Fig. 9. Each cutter 1 -15a has interlocking faces 13a to engage corresponding faces 12a on the vbody 1a, and each cutter has a removable cutting point 24 as indicated in Figs. 9 and 12. The cross-key 17a ters, so that the force of the spring 4a will be applied thereto to hold the cutters in their normal positions, as showninfull lines in Fig. 9. The cutters 'may have shoulders 20a, against which the breakable spacers33a maybe set, or the spacers may be set between the interlocking members 13a and 12a, as indicated in dotted lines in Fig. 9, if desired. The operation of this form of my invention is essentially the same as thatv ofthe first described form, stood by refer-ence to the drawings, and therefore a detail description of the operation of the same is believed to be unnecessary.

enters the slots 16a of the cutand will be readily undery connection with the accompanying drawings,

it is believed the complete construction, opv l of the -invention will be manifest t6 those skilled in the art, and I desire it understood, thatl the forms ndisclosed in the drawings are the preferred eration and advantages arrangements, although, I do not wish to be limited thereto.

What I claim is 1. In an under-reamer, a body portion having radial chambers, the side walls of which are provided with grooves whose lower extremities are` blind, cutters mounted in said chambers and having trunnions to` enter said grooves, said body portion at its lower extremity having l'an interlocking face, said cutters each'having interlocking faces to interlock with said body face, and means continuously tending to hold said cutters interlocked with said body 2. In a reamer, a body having radially disp cluding trunnions mounted in said grooves,

said cutters having heads, a cross key -passing through 'said cutters and a spring actuated rod device connect-ing With said key and continuously tending to move said cutters'upwardly to bring said cutter heads into engagement with the under-face of said body, the cutter heads and said body-tace having interprojecting portions.

3. ln an under-reamer, a body portion having'radia'l chambers, t-he side Walls of Which are provided With grooves Whose lovver extremities are blind, cutters mounted in said chambers and having trunnions to enter said grooves, said body portion at its lovver extremity having an interlocking face, said cutters each having interlocking faces to interlock with said body face, and means continuously tending to hold said cutters interlocked with said body, said cutters being foldable into the diametric dimensions ofLsaid body and means for holding said cutters in their folded position 'against the tension of said'continuously acting cutter moving means.

4. In 'a reamer, `aA body having radially disposed cutter receiving chambers, the side Walls of said chambers having -grooves, one end of each of which opens outwardly and the other end is blind,- cutters having bud" portions held in said chambers and incuding trunnions mountedy in said grooves, said cutters having heads, across key passing through said cutters rand a spring actuated rod device connecting with said key and continuously tending to move said cuttersupvvardly to bring saidfcutter heads into engagement with the under-face of said body, the cutter heads and said body-face having interprojecting portions, said cutters being foldable into the diametric dimensions of said body, and means .for holding said cutters in their folded'position against the tension of said continuously acting cutter moving means;

5. In an under-reamer for oil Wells, a

main body having a pair of oppositely dis- Qfposed radial chambers or pockets, cutters mounted in said pockets and having projecting heads, each of said cutter heads and said body having interlocking portions to register with one another when saidl cutters are l in their Working positions, and spring actu` ated means for holding said cutters in their Working positions, lsaid main body having grooves, and said cutters-having portions projecting into said grooves, said body and grooves includingk provisions cooperating With'said projecting portions to retain said cutters in connection With said body indeably mount-ed in each of said chambers, said body having its lower face provided with cutter interlocking portions, each of said cutters having interlocking heads for engaging the respect-ive interlocking portions, and a single means connecting all ot said cutters and continuously tending to move said cutters into said pockets with their interlocking portions into inteilocked relation With sai body interlocking portions, said body having grooves of substantially l.shape in elevation, and said cutters having trunnions to enter said grooves, the entrant ends of said grooves being of less Width than the remaining portions of the respective grooves, and said trunnions having a dimension corresponding with the entrant portion of the respective grooves in virtue of which said4 nions to enter said grooves, said body `portion -and said cutter having 'interlocking' t'aces, and means continuously tending to hold said cutter interlocked with said body,l said grooves and said trunnions coopera-ting to hold said cutter connected with saidbody, and said grooves having provisions to r .e tain said cutter in connection Iwith said body irrespective of said means that continu*- ously tends to hold said cutters interlocked with said body.

8. ln an under-reamer, a body having a cutter receiving chamber opening at the sidethe,fiside yvalls of said chamber having grooves one end of each of which opens outwardly and the lower end is blind, a cutter having a body port-ion held in said chamber and including trunnions,mounted in said grooves, said-cutter 'having a head, said cutter-head and said body having inter-projecting portions to interlock said cutter and body, and yieldable means for holding said cutter interlocked with said body.

.9. In an `under-reamer, a body having a i grooves, one end of each of which o ensJ outwardly and the other end is blin .a cutter having a body portion held in said chamber and including trunnions mounted in said grooves, said cutter having a head,`

said cutter-head and said body having in@ portion Sti terproject-ing portions to interlock said cutv,

t-er and body, and yieldable means for holding `Said cutter interlocked wan-Said body,

said body grooves having provisions for r e taining said cutter 1n connectlon with-sald body upon failure of saidlast named means body having a cutter chamber, a cutterremovablyl retaining said held in said chamber, resilient means for ret-aining said cutter in operative position, and asingle devicefor positively connecting said cutter to said body and for I cutter in connection With said body in the event that said resilient retain,- ing meansbecomes broken or inoperative, a

removable cutter point for said cutter andy means for removably securing said cutter point in positlon.

12. In an under-reamer Jfor wells, a body l portion having radial chambers, cutters piyotally and slidably mounted at one end 1n said chambers, said body portion having a central peak portion and side interlocking projections, said cutters each having interlocking portions to coperatively engage said peak ortion and said interlocking projections o said body portion, said eak portion extending below the planeo the lower edges jections,l and means continuously tending to hold 1said cutter interlocking portions interlocked with the corresponding partsk of said body, theplower faces of said' cutters lying in planes extending from said central peak portion and diverging downwardly and laterally are in their cutting positions, as shown and described.'

13. In an under-reamer for wells, a body portion having a central peak portion and -vside interlockin project-ions merging with said central Apea portion, said central eak portion extending side interlockin projections, cutters mounted on said body and having interlocking portions to cooperatively engage said peak portion and said side interlocking projections, when in their operative position and the end of said peak portion lying in substantially the same transverse plane, the bottom faces of said cutters extending from the cutting points toward said peak portion and converging upwardly thereto substantially as shown and described.

CLAYTON E. `FREDERICKSON.

Witnesses:

H. B. DENsoN,

substantially therefrom when said cutters of said side interlocking p'ro- 'i downwardly beyond said the cutting points of said cutters 

